This invention relates to compositions for use as corrosion inhibitors, lubricants and emulsifiers, particularly primary alkanoletheramides made from dimerized or trimerized tall oil fatty acids and from an aminoalkoxyalcohol such as aminoethoxyethanol, and compositions containing fatty acid mono-amides and the primary alkanoletheramides of dimer or trimer acids.
Alkanolamides are used in the metalworking industry as corrosion inhibitors, lubricants and emulsifiers. The industry often uses C10 to C24 fatty acids for production of these amides, including use of tall oil fatty acids (TOFA-) which consist mainly of mixtures of saturated, mono-unsaturated and di-unsaturated C18 fatty acids. In the past the industry has typically used amides from secondary alkanolamines due to the tendency for these amides to remain free of precipitated solids during storage. These xe2x80x9cclearxe2x80x9d liquids have the advantage of being easy to handle and dispense. There now exists a push in the industry to move away from use of secondary alkanolamines due to health concerns. Primary alkanolamines present adequate replacements in many applications. However, fatty amides of primary alkanolamines tend to precipitate out solids at ambient temperatures and in some cases become completely solid. This makes these mono-substituted alkanolamides difficult to handle.
This invention provides a solution to one or more of the problems and disadvantages discussed above. The current invention relates to a composition containing an amide of a primary amine that remains clear of suspended solids during storage, making mixtures containing the additive particularly useful to the metalworking industry. The composition contains an amide formed by the condensation of a primary amine and a dimerized or trimerized fatty acid. Preferably, the primary amine is an alkanoletheramine such as of formula H(OA)aNH2 wherein A is independently in each occurrence a diradical of ethyl or propyl and xe2x80x9caxe2x80x9d is from 2 to about 30. The dimer and trimer acids are produced by linking two or three monounsaturated acid molecules at the site of unsaturation resulting in loss of unsaturation and various linkages joining the two or three molecules at some point on their fatty carbon chains. The condensation reaction of this acid with aminoethoxyethanol, for instance, produces a molecule with two or three substituted amide functionalities and two to three adjoining fatty acid chains. Advantageously, when added to an amide of a primary alkanolamine and monomeric fatty acid, these molecules are able to prevent crystallization of the amide mixture. Formation of a dimer amide may be represented by the following reaction scheme: 
In this scheme, the total number of carbons in the fatty acid may vary widely (each of x, y, t and u may vary from 1 to 25) and in one embodiment is 36. This is but one possible structure arrived at by dimerization and is not intended to be limiting in any way. The product shown is derived from aminoethoxyethanol, but other amines may be employed.
Formation of a trimer amide may be represented by the following reaction scheme: 
In this scheme, the total number of carbons in the fatty acid may vary widely (each of x, y, t, u, r and s may vary from 1 to 25) and in one embodiment is 54. This is but one possible structure arrived at by trimerization and is not intended to be limiting in any way. The product shown is derived from aminoethoxyethanol, but other amines may be employed.
In one broad respect, this invention is the reaction product of a mono-amine and a dimerized or trimerized fatty acid. In another broad respect, this invention is a manufacturing process, comprising: contacting an amine and a dimerized or trimerized fatty acid to form a reaction product. In one broad respect, this invention is a primary alkanoletheramide of a dimerized or trimerized fatty acid. In another broad respect, this invention is a composition comprising the reaction product of a primary aminoalkoxyalkanol and a dimerized or a trimerized fatty acid. A representative, non-limiting example of a suitable aminoalkoxyalkanol is aminoethoxyethanol. In another broad respect, this invention is a composition containing a mono-amide made from a primary alkanolamine and a poly-amide made from a dimer or trimer acid and from a primary amine.
In another broad respect, this invention is a composition comprising a compound of formula 
wherein each of x, y, t and u may vary from 1 to 25 and wherein R is an alkanol or an ether-alkanol radical.
In another broad respect, this invention is a composition comprising a compound of formula 
wherein each of x, y, t, u, r and s may vary from 1 to 25 and wherein R is an alkanol or an ether alkanol radical.